The present invention relates to a level control system for controlling the metal level in continuous or semi-continuous casting equipment, for instance casting equipment for the production of billets or ingots of aluminum, which casting equipment includes a casting mold with an upwardly open supply opening for receiving molten metal and a supply gutter or the like, with an outlet arranged above the supply opening for transfer of the molten metal from a holding furnace or the like.
When casting metal continuously or semi-continuously as mentioned above, a metal flow control system based on the use of floats is most commonly used today. This system possesses limited possibilities of controlling the level of molten metal during the casting operation and no possibilities to control supply of molten metal during start-up of the casting operation. Besides, the control for such a system is slow, which, inter alia, results in an uneven quality of the cast metal body. Especially when casting roll ingots, the metal supply at the starting of casting and thereby the level of molten metal in the casting mold is of very great importance, since most of the problems which arise at later stages of casting are caused by these initial conditions.